Communication device and communication method

ABSTRACT

To provide a mechanism capable of improving communication efficiency even in communication before allocation of an AID. 
     A communication device including: a communication unit configured to transmit a first frame including a second association identifier decided by a communication device to which a first association identifier is allocated and receive a second frame including information related to the second association identifier.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.16/436,942, filed Jun. 11, 2019, which is a continuation of U.S.application Ser. No. 15/745,268, filed Jan. 16, 2018 (now U.S. Pat. No.10,362,150), which is based on PCT filing PCT/JP2016/070873, filed Jul.14, 2016, and claims priority to JP 2015-177516, filed on Sep. 9, 2015,the entire contents of each are incorporated herein by reference.

TECHNICAL FIELD

The present disclosure relates to a communication device and acommunication method.

BACKGROUND ART

In recent years, wireless local area networks (LANs) typified byInstitute of Electrical and Electronics Engineers (IEEE) 802.11 havespread. In addition, with the wireless LANs, products corresponding tothe wireless LANs (hereinafter also referred to as wirelesscommunication devices) have also increased. When wireless communicationdevices increase, there is a high possibility of communicationefficiency deteriorating. Therefore, it is desirable to improve thecommunication efficiency.

Thus, Patent Literature 1 discloses the invention related to a method ofimproving communication efficiency by reducing header information of aframe (packet). Specifically, instead of a global identifier such as amedia access control (MAC) address, a local identifier such as anassociation identifier (AID) is stored as a part of the headerinformation. Since the AID is data shorter than the MAC address, thesize of the header information is contracted, thereby improvingcommunication efficiency.

CITATION LIST Patent Literature

-   Patent Literature 1: JP 2014-520426T

DISCLOSURE OF INVENTION Technical Problem

In the invention disclosed in Patent Literature 1, however, it isdifficult to improve communication efficiency in communication beforeallocation of an AID. For example, in a communication device in which anAID is not allocated, it is difficult to execute the above-describedcommunication in which an AID is used as a part of the headerinformation of a frame instead of a MAC address.

Accordingly, the present disclosure proposes a mechanism capable ofimproving communication efficiency even in communication beforeallocation of an AID.

Solution to Problem

According to the present disclosure, there is provided a communicationdevice including: a communication unit configured to transmit a firstframe including a second association identifier decided by acommunication device to which a first association identifier isallocated and receive a second frame including information related tothe second association identifier.

In addition, according to the present disclosure, there is provided acommunication device including: a communication unit configured toreceive a first frame including a second association identifiergenerated by a communication device to which a first associationidentifier is allocated and transmit a second frame includinginformation related to the second association identifier.

In addition, according to the present disclosure, there is provided acommunication method including: by a communication unit, transmitting afirst frame including a second association identifier decided by acommunication device to which a first association identifier isallocated; and receiving a second frame including information related tothe second association identifier.

In addition, according to the present disclosure, there is provided acommunication method including: by a communication unit, receiving afirst frame including a second association identifier generated by acommunication device to which a first association identifier isallocated; and transmitting a second frame including information relatedto the second association identifier.

Advantageous Effects of Invention

According to the present disclosure, as described above, it is possibleto provide a mechanism capable of improving communication efficiencyeven in communication before allocation of an AID. Note that the effectsdescribed above are not necessarily limitative. With or in the place ofthe above effects, there may be achieved any one of the effectsdescribed in this specification or other effects that may be graspedfrom this specification.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a sequence diagram conceptually illustrating an example of anassociation process of the related art.

FIG. 2 is a diagram illustrating an example of an overall configurationof a communication system according to a first embodiment of the presentdisclosure.

FIG. 3 is a block diagram illustrating an example of an overallfunctional configuration of a communication device according to theembodiment.

FIG. 4 is a diagram illustrating an example of a setting range of atentative AID according to the embodiment.

FIG. 5 is a diagram illustrating a configuration example of a tentativeAID notification frame according to the embodiment.

FIG. 6 is a diagram illustrating a configuration example of a VHT NDPannouncement frame.

FIG. 7 is a diagram illustrating a configuration example of abeamforming report poll (BRP) frame.

FIG. 8 is a diagram illustrating a configuration example of a VHTcompressed beamforming (VCB) frame.

FIG. 9 is a diagram illustrating a configuration example of a frame witha VHT PPDU format.

FIG. 10 is a sequence diagram conceptually illustrating an overview of atentative AID registration process according to the embodiment.

FIG. 11 is a sequence diagram conceptually illustrating the details ofthe tentative AID registration process according to the embodiment.

FIG. 12 is a sequence diagram conceptually illustrating an overview of asounding process using the tentative AID according to the embodiment.

FIG. 13 is a sequence diagram conceptually illustrating the details ofthe sounding process using the tentative AID according to theembodiment.

FIG. 14 is a flowchart conceptually illustrating a tentative AIDregistration process in an STA according to the embodiment.

FIG. 15 is a flowchart conceptually illustrating a tentative AIDregistration process in an AP according to the embodiment.

FIG. 16 is a flowchart conceptually illustrating transmission andreception processes using the tentative AID in an STA according to theembodiment.

FIG. 17 is a flowchart conceptually illustrating transmission andreception processes using the tentative AID in an AP according to theembodiment.

FIG. 18 is a sequence diagram conceptually illustrating an overview ofan association process using a tentative AID according to a secondembodiment of the present disclosure.

FIG. 19 is a flowchart conceptually illustrating a tentative AIDregistration process and an association process in an STA according tothe embodiment.

FIG. 20 is a flowchart conceptually illustrating a tentative AIDregistration process and an association process in an AP according tothe embodiment.

FIG. 21 is a block diagram illustrating an example of a schematicconfiguration of a smartphone.

FIG. 22 is a block diagram illustrating an example of a schematicconfiguration of a car navigation device.

FIG. 23 is a block diagram illustrating an example of a schematicconfiguration of a wireless access point.

MODE(S) FOR CARRYING OUT THE INVENTION

Hereinafter, (a) preferred embodiment(s) of the present disclosure willbe described in detail with reference to the appended drawings. Notethat, in this specification and the appended drawings, structuralelements that have substantially the same function and structure aredenoted with the same reference numerals, and repeated explanation ofthese structural elements is omitted.

Further, in this specification and the drawings, there are also cases inwhich a plurality of components having substantially the same functionand structure are distinguished by adding different numbers to the endof the same reference numeral. For example, a plurality of componentshaving substantially the same function are distinguished as necessarylike an STA 10A and an STA 10B. However, in a case where it isunnecessary to distinguish components having substantially the samefunction and structure, only the same reference numeral is added. Forexample, in a case where it is unnecessary to particularly distinguishthe STA 10A and the STA 10B, they are referred to as simply as an “STA100.”

Moreover, the description will be made in the following order.

-   1. Problem of technology of related art-   2. First embodiment (sounding process using tentative AID)-   2-1. Configuration of communication system-   2-2. Configuration of communication device-   2-3. Functional details of communication device-   2-4. Process of communication device-   2-5. Conclusion of first embodiment-   3. Second embodiment (association process using tentative AID)-   3-1. Functional details of communication device-   3-2. Process of communication device-   3-3. Conclusion of second embodiment-   4. Application examples-   5. Conclusion

1. Problem of Technology of Related Art

First, a problem of a technology of the related art will be described.

Communication devices of the related art have a wireless LANcommunication function to transmit and receive frames. In addition, thecommunication devices of the related art include communication devicesoperating as stations (STAs) (hereinafter also referred to as STAs 10)and a communication device operating as an access point (AP)(hereinafter also referred to as an AP 20). Moreover, communication fromthe STA 10 to the AP 20 is also referred to as an uplink (UL) andcommunication from the AP 20 to the STA 10 is also referred to as adownlink (DL).

A frame transmitted or received by a wireless communication device ofthe related art generally includes a header including destinationinformation of the frame and a data portion including data to bedelivered. In the related art, as described above, a technology forachieving an improvement in communication efficiency by reducing thesize of the header has been proposed. Specifically, a technology inwhich an AID is used as destination information included in the headerinstead of a MAC address has been proposed.

In addition, other technologies for achieving an improvement incommunication efficiency using an AID have been proposed. For example,in the IEEE 802.11ac standard, a very high throughput (VHT) physicallayer convergence protocol (PLCP) protocol data unit (PPDU) including anidentifier generated from a part of the AID is defined. A frame with theVHT PPDU format is transmitted from the AP 20 to the STA 10. The STA candetermine whether the frame with the VHT PPDU format is destined for theself-device at a stage at which the header of the received frame withthe VHT PPDU format is decoded. Accordingly, it is possible toaccelerate a communication process and improve a communicationthroughput because of a reduction in a communication amount.

Here, the AID can be allocated to a communication device through anassociation process. Specifically, the AP 20 receiving an associationrequest from the STA 10 allocates the AID to the STA 10 by setting theAID in the STA 10 and notifying the STA 10 of the set AID. Further, anassociation process of the related art will be described in detail withreference to FIG. 1 . FIG. 1 is a sequence diagram conceptuallyillustrating an example of the association process of the related art.

First, an STA 10A transmits an association request frame to the AP 20when a connection request with the AP 20 occurs (step S31).

The AP 20 receiving the association request frame transmits anacknowledgment (ACK) (confirmation response) to the association requestframe (step S32) and sets AID #1 (step S33). Specifically, the AP 20decides an AID in the STA 10A which is a transmission source of theassociation request frame without overlapping in a setting range of theAID prepared in advance.

Subsequently, the AP 20 transmits an association response frameincluding the set AID to the STA 10A (step S34).

The STA 10A receiving the association response frame transmits aconfirmation response frame for the association response frame (stepS35) and registers the allocated AID #1 (step S36).

In this way, the AID can be allocated to the STA 10 through theassociation process executed between the STA 10 and the AP 20.Accordingly, unless the association process is executed later, it isdifficult to execute communication using the above-described AID.

Moreover, the association process is individually executed for each STA10. For example, as illustrated in FIG. 1 , an association process ofthe STA 10B (steps S37 to S42) and an association process of the STA 10C(steps S43 to S48) are executed in sequence after the associationprocess of the STA 10A ends.

Then, after the association processes with all the STAs 10 end, that is,the allocation of the AIDs ends, communication in which the AIDs areused can be executed. For example, in a case in which the communicationwith each STA 10 is executed after the end of the association processesof the STAs 10A to 10C, a VHT null data packet (NDP) announcement frameillustrated in FIG. 1 is transmitted as a part of communication executedto collect channel information of the STAs 10A to 10C to be describedbelow.

In this way, in a case in which association requests to the plurality ofSTAs 10 occur, the association process is executed for each STA 10.Therefore, to execute the association process, the STA 10 is caused towait. Thus, an overhead for the association process increases andcommunication efficiency deteriorates.

Accordingly, the present disclosure proposes a mechanism capable ofimproving communication efficiency even in communication before an AIDis allocated. Hereinafter, the details of the mechanism will bedescribed. Moreover, to facilitate the description, communicationdevices according to first and second embodiments are distinguished fromeach other by suffixing numbers corresponding to the embodiments, as incommunication devices 100-1 and 100-2.

2. First Embodiment (Sounding Process Using Tentative AID)

The problem of the technology of the related art has been describedabove. Next, a communication system according to the first embodiment ofthe present disclosure will be described. The communication systemaccording to the embodiment executes a sounding process of a channel inwhich a tentative AID to be described below is used.

2-1. Configuration of Communication System

First, a configuration of the communication system according to thefirst embodiment of the present disclosure has been described withreference to FIG. 2 . FIG. 2 is a diagram illustrating an example of anoverall configuration of the communication system according to the firstembodiment of the present disclosure.

The communication system according to the embodiment includes STAs 100-1and AP 200-1. For example, the communication system according to theembodiment includes STAs 100-1A to 100-1C and the AP 200-1, asillustrated in FIG. 2 . The AP 200-1 and the STAs 100-1A to 100-1C cancommunicate with each other. Hereinafter, in a case in which it is notnecessary to distinguish the STAs 100-1 and the AP 200-1 from eachother, the STAs 100-1 and the AP 200-1 are also simply referred to asthe communication devices 100-1 (200-1).

2-2. Configuration of Communication Device

Next, a functional configuration of the communication device 100-1(200-1) according to the embodiment will be described with reference toFIG. 3 . FIG. 3 is a block diagram illustrating an example of an overallfunctional configuration of the communication device 100-1 (200-1)according to the embodiment.

The communication device 100-1 (200-1) includes a data processing unit110 (210), a control unit 120 (220), and a wireless communication unit130 (230) as a communication unit, as illustrated in FIG. 3 .

(Data Processing Unit)

As illustrated in FIG. 3 , the data processing unit 110 (210) includesan interface unit 111, a transmission buffer 112, a transmission frameconstruction unit 113, a received frame analysis unit 114, and areception buffer 115.

The interface unit 111 is an interface connected to another functionalconfiguration of the communication device 100-1 (200-1). Specifically,the interface unit 111 executes the other functional configuration, forexample, receives data desired to be transmitted from an application orsupplies reception data to the application.

The transmission buffer 112 stores data to be transmitted. Specifically,the transmission buffer 112 stores data obtained by the interface unit111.

The transmission frame construction unit 113 generates a frame to betransmitted. Specifically, the transmission frame construction unit 113generates data to be stored in the transmission buffer 112 or generatesa frame on the basis of control information set by the control unit 120(220). For example, the transmission frame construction unit 113executes a process of generating a frame (a packet) from data acquiredfrom the transmission buffer 112 and executing, for example, addition ofa media access control (MAC) header for MAC and addition of an errordetection code to the generated frame.

The received frame analysis unit 114 analyzes a received frame.Specifically, the received frame analysis unit 114 determines adestination of a frame received by the wireless communication unit 130(230) and acquires data or control information included in the frame.For example, the received frame analysis unit 114 acquires data includedin a received frame by executing, for example, analysis of a MAC header,detection and correction of a code error, and a reordering process onthe received frame.

The reception buffer 115 stores received data. Specifically, thereception buffer 115 stores the data acquired by the received frameanalysis unit 114.

(Control Unit)

As illustrated in FIG. 3 , the control unit 120 (220) includes aprocessing control unit 121 and a signal control unit 122.

The processing control unit 121 controls an operation of the dataprocessing unit 110 (210). Specifically, the processing control unit 121controls occurrence of communication. For example, when a communicationconnection request occurs, the processing control unit 121 causes thedata processing unit 110 to generate a frame related to a connectionprocess or a certification process such as an association process or anauthentication process.

In addition, the processing control unit 121 controls the generation ofthe frame on the basis of a data storage situation, a received-frameanalysis result, or the like in the transmission buffer 112. Forexample, in a case in which data is stored in the transmission buffer112, the processing control unit 121 instructs the transmission frameconstruction unit 113 to generate a data frame in which the data isstored. In addition, in a case in which the received frame analysis unit114 confirms that a frame is received, the processing control unit 121instructs the transmission frame construction unit 113 to generate aconfirmation response frame as a response to the received frame.

The signal control unit 122 controls an operation of the wirelesscommunication unit 130 (230). Specifically, the signal control unit 122controls transmission and reception processes of the wirelesscommunication unit 130 (230). For example, the signal control unit 122causes the wireless communication unit 130 (230) to set parameters fortransmission and reception on the basis of an instruction of theprocessing control unit 121.

(Wireless Communication Unit)

As illustrated in FIG. 3 , the wireless communication unit 130 (230)includes a transmission processing unit 131, a reception processing unit132, and an antenna control unit 133.

The transmission processing unit 131 performs a frame transmissionprocess. Specifically, the transmission processing unit 131 generates asignal to be transmitted on the basis of a frame supplied from thetransmission frame construction unit 113. More specifically, thetransmission processing unit 131 generates a signal related to a frameon the basis of a parameter set by an instruction from the signalcontrol unit 122. For example, the transmission processing unit 131generates a symbol stream by encoding, interleaving, and modulating aframe supplied from the data processing unit 110 in conformity withcoding and modulation schemes or the like instructed by the control unit120. In addition, the transmission processing unit 131 converts a signalrelated to the symbol stream obtained through a process on the frontstage into an analog signal and executes amplification, filtering, andfrequency up-conversion on the analog signal.

Moreover, the transmission processing unit 131 may execute a framemultiplexing process. Specifically, the transmission processing unit 131executes a process related to frequency division multiplexing or spacedivision multiplexing.

The reception processing unit 132 executes a frame reception process.Specifically, the reception processing unit 132 restores a frame on thebasis of a signal supplied from the antenna control unit 133. Forexample, the reception processing unit 132 acquires a symbol stream byexecuting reverse processes to the processes at the time of transmissionof the signal, for example, frequency down-conversion, digital signalconversion, and the like, on a signal obtained from the antenna. Inaddition, the reception processing unit 132 acquires a frame bydemodulating and decoding the symbol stream obtained through the processon the front stage and supplies the acquired frame to the dataprocessing unit 110 (210) or the control unit 120 (220).

Moreover, the reception processing unit 132 may execute a processrelated to demultiplexing of the multiplexed frame. Specifically, thereception processing unit 132 performs a process related todemultiplexing on a frame subjected to frequency division multiplexingor space division multiplexing.

In addition, the reception processing unit 132 may estimate a channelgain. Specifically, the reception processing unit 132 calculates complexchannel gain information from a preamble portion or a training signalportion of a signal obtained from the antenna control unit 133.Moreover, the calculated complex channel gain information is used in theprocess related to frame multiplexing and a process of framedemultiplexing.

The antenna control unit 133 transmits and receives a signal via atleast one antenna. Specifically, the antenna control unit 133 transmitsa signal generated by the transmission processing unit 131 via theantenna and supplies a signal received via the antenna to the receptionprocessing unit 132. In addition, the antenna control unit 133 mayexecute control related to space division multiplexing.

Moreover, although not illustrated in FIG. 3 , the communication device100-1 (200-1) may include an input unit and an output unit connected viathe interface unit 111. For example, the input unit acquires inputinformation or the like of a user from an input device such as akeyboard or a mouse. Then, the input information or the like is storedas data in the transmission buffer via the interface unit 111. Inaddition, data stored in the reception buffer is supplied to the outputunit via the interface unit 111 and the output unit causes a display, aspeaker, or the like to output an image, audio or music, or the like onthe basis of supplied data.

2-3. Functional Details of Communication Device

Next, functional details of the communication device 100-1 (200-1)according to the first embodiment of the present disclosure will bedescribed.

(A. Functional Details of STA)

First, the functional details of the STA 100-1 will be described.

(A-1. Decision of Tentative AID)

The STA 100-1 decides a second association identifier (hereinafter alsoreferred to as a tentative AID). Specifically, the control unit 120decides a tentative AID used in the self-device within a setting rangeof the tentative AID. More specifically, the control unit 120 decidesthe tentative AID that the self-device uses within the setting range ofthe tentative AID different from a setting range of an AID. For example,in a case in which the AP 200-1 is found on the basis of reception of abeacon frame or the like transmitted from the AP 200-1 or connectionwith the AP 200-1 is performed in this case, the control unit 120decides the tentative AID that the self-device uses among tentative AIDsprepared separately from the setting range of the AID. Further, aprocess of deciding the tentative AID will be described with referenceto FIG. 4 . FIG. 4 is a diagram illustrating an example of a settingrange of a tentative AID according to the embodiment.

First, the setting range of the AID is generally defined in conformitywith a standard. For example, as illustrated in FIG. 4 , the settingrange of the AID is 0x0001 to 0x07D7 in the IEEE 802.11 standard.

On the other hand, the setting range of the tentative AID according tothe embodiment is prepared separately from the setting range of the AID.For example, as illustrated in FIG. 4 , the setting range of thetentative AID is 0x0800 to 0x08FF. The control unit 120 decides atentative AID that the self-device uses from the setting range of thetentative AID. Moreover, of course, the setting range of the tentativeAID may be another setting range different from the setting rangeillustrated in FIG. 4 .

In addition, the control unit 120 decides a tentative AID different fromtentative AIDs used in the other STAs 100-1 as the tentative AID of theself-device. For example, the control unit 120 causes a storage unit tostore the tentative AIDs included in received frames of the other STAs100-1 and decides a tentative AID different from the stored tentativeAIDs of the other STAs 100-1 as a tentative AID of the self-device.Moreover, a notification of the tentative AIDs used in the other STAs100-1 may be issued by the AP 200-1. For example, the AP 200-1 transmitsa beacon frame or the like including information indicating thetentative AID registered in the AP 200-1. The STA 100-1 receiving thebeacon frame or the like decides a tentative AID other than theregistered tentative AIDs as a tentative AID of the self-device.

In addition, the tentative AID is decided for each AP 200-1. Forexample, whenever the AP 200-1 is found or in a case in which connectionwith the AP 200-1 is desired, the control unit 120 manages the tentativeAID for each AP 200-1 by deciding a tentative AID to be applied to theAP 200-1 and associating the decided tentative AID with the AP 200-1.

Moreover, the example in which the setting range of the tentative AID isdifferent from the setting range of the AID has been described, but thetentative AID may be decided from the setting range of the AID. Forexample, the control unit 120 decides the tentative AID of theself-device from the setting range 0x0001 to 0x07D7 of the AID describedabove. Moreover, as in a case in which the tentative AID is decided fromthe setting range of the tentative AID, the control unit 120 may decidean AID other than the AID already set in another STA as the tentativeAID of the self-device.

(A-2. Notification and Registration of Tentative AID)

The STA 100-1 transmits a tentative AID notification frame as a firstframe including the tentative AID. Specifically, the control unit 120causes the data processing unit 110 to generate the tentative AIDnotification frame including information indicating the decidedtentative AID. Then, the wireless communication unit 130 transmits thegenerated tentative AID notification frame to the AP 200-1. Further, thetentative AID notification frame according to the embodiment will bedescribed in detail with reference to FIG. 5 . FIG. 5 is a diagramillustrating a configuration example of the tentative AID notificationframe according to the embodiment.

As illustrated in FIG. 5 , the tentative AID notification frame includesfields such as Frame Control, Duration, Address1 to Address3, SequenceControl, Address4, HT Control, Management Frame Body, and Frame CheckSequence (FCS). Moreover, in FIG. 5 , an example in which the tentativeAID notification frame is a management frame is illustrated, but thetentative AID notification frame may be another type of frame such as acontrol frame or a data frame.

As illustrated in FIG. 5 , Management Frame Body includes a TentativeAID Information Element field. The Tentative AID Information Elementfield includes fields such as Element ID, Length, and Tentative AID.Information indicating a tentative AID is stored in the Tentative AIDfield.

In addition, the STA 100-1 registers a tentative AID. Specifically, whena confirmation response frame for a tentative AID notification frame isreceived, the control unit 120 registers the tentative AID included inthe tentative AID notification frame. For example, the control unit 120causes the storage unit to store the information indicating thetentative AID included in the tentative AID notification frame by whicha confirmation response is received.

Moreover, in a case in which the confirmation response frame is notreceived, the STA 100-1 changes the tentative AID and retransmits thetentative AID notification frame. Specifically, the control unit 120causes the wireless communication unit 130 to transmit the tentative AIDnotification frame including the tentative AID different from thetentative AID included in the tentative AID notification frame by whichthe confirmation response frame has not been received. For example, in acase in which the confirmation response frame is not received before apredetermined time has passed from the transmission of the tentative AIDnotification frame, the control unit 120 re-decides the tentative AIDand causes the data processing unit 110 to generate the tentative AIDnotification frame including the re-decided AID. Then, the generatedtentative AID notification frame is transmitted by the wirelesscommunication unit 130.

On the other hand, since there is a possibility of the tentative AIDnotification frame not being received, the STA 100-1 may retransmit thetentative AID notification frame without changing the tentative AID.

(A-3. Sounding Process Using Tentative AID)

The STA 100-1 receives a frame related to a channel information requestas a second frame including information related to the tentative AID.Specifically, the frame related to the channel information requestincludes a frame for issuing a notification of transmission of a channelinformation request frame (hereinafter also referred to as a priornotification frame).

More specifically, when the prior notification frame is received fromthe AP 200-1, the data processing unit 110 acquires informationindicating a tentative AID included in the prior notification frame. Thecontrol unit 120 determines whether the tentative AID of the self-deviceis included in the acquired information indicating the tentative AID. Ina case in which the control unit 120 determines that the tentative AIDof the self-device is included, the control unit 120 causes the wirelesscommunication unit 130 to prepare a sounding process and wait for thechannel information request frame. Then, when the channel informationrequest frame is received from the AP 200-1, the wireless communicationunit 130 executes the sounding process such as estimation of a channelgain.

For example, the prior notification frame is a VHT NDP Announcementframe and the channel information request frame is a null data packet(NDP) frame. Further, the prior notification frame according to theembodiment will be described in detail with reference to FIG. 6 . FIG. 6is a diagram illustrating a configuration example of the VHT NDPAnnouncement frame.

As illustrated in FIG. 6 , the VHT NDP Announcement frame includesfields such as Frame Control, Duration/ID, Receive Address, TransmitAddress, Sounding Sequence, n pieces of STA Info, and FCS. In the STAInfo field, information regarding the STA 100-1 which is a transmissiontarget of a subsequent NDP frame or a beamforming report poll (BRP)frame to be described below is stored.

As illustrated in FIG. 6 , the STA Info field includes fields such asAID, Feedback Type, and number of columns (NC) Index. Here, in the AIDfield, information indicating an AID is stored in the related art, butinformation indicating a tentative AID is stored in the embodiment.Moreover, in a case in which an AID has already been allocated in theSTA 100-1 which is a transmission target, the information indicating theAID may be stored or the information indicating the tentative AID andthe information indicating the AID may coexist in the VHT NDPAnnouncement frame.

In addition, when the channel information request frame is received, theSTA 100-1 transmits the channel information notification frame as aresponse to the channel information request frame. Specifically, whenthe NDP frame is received, the STA 100-1 transmits the channelinformation notification frame including the channel informationobtained through the sounding process as a response to the NDP frame tothe AP 200-1.

Moreover, when another channel information request frame destined forthe self-device and different from the NDP frame is received, the STA100-1 may transmit the channel information notification frame as aresponse to the other channel information request frame. Morespecifically, when the other channel information request frame isreceived from the AP 200-1, the data processing unit 110 acquiresinformation indicating the tentative AID included in the other channelinformation request frame. The control unit 120 determines whether thetentative AID of the self-device is included in the acquired informationindicating the tentative AID. In a case in which the control unit 120determines that the tentative AID of the self-device is included, thecontrol unit 120 causes the data processing unit 110 to generate thechannel information notification frame including channel informationacquired through the sounding process. Then, the wireless communicationunit 130 transmits the generated channel information notification frameto the AP 200-1.

For example, the other channel information request frame is a BRP frameand the channel information notification frame is a VHT compressedbeamforming (VCB) frame. Further, the channel information request frameand the channel information notification frame according to theembodiment will be described with reference to FIGS. 7 and 8 . FIG. 7 isa diagram illustrating a configuration example of the BRP frame. FIG. 8is a diagram illustrating a configuration example of the VCB frame.

As illustrated in FIG. 7 , the BRP frame includes fields such as FrameControl, Duration/ID, Receive Address, Transmit Address, FeedbackSegment Retransmission Bitmap, and FCS. The fields are substantially thesame as the fields of the BRP frame of the related art, and thereforethe description thereof will be omitted. Moreover, the informationindicating the tentative AID may be stored in the Received Addressfield.

In addition, as illustrated in FIG. 8 , the VCB frame includes fieldssuch as Category, VHT Action, VHT Compressed Beamforming Report, andMulti User (MU) Exclusive Beamforming Report. The fields aresubstantially the same as the fields of the BRP frame of the relatedart, and therefore the description thereof will be omitted. Moreover,the VCB frame is a frame for which a confirmation response is notrequested.

(A-4. Data Transmission and Reception Using Tentative AID)

The STA 100-1 receives a frame including the tentative AID asdestination information of a frame. Specifically, the STA 100-1 executesa frame reception process on the basis of whether the tentative AIDincluded in the received frame is the tentative AID of the self-device.

More specifically, when a frame with the VHT PPDU format is receivedfrom the AP 200-1, the wireless communication unit 130 acquires thetentative AID included in the header of the frame. Subsequently, thewireless communication unit 130 determines whether the acquiredtentative AID is the tentative AID of the self-device. When the wirelesscommunication unit 130 determines that the acquired tentative AID is thetentative AID of the self-device, the wireless communication unit 130receives the frame with the VHT PPDU format up to the tail of the frameand provides a data frame obtained in the reception to the dataprocessing unit 110. Moreover, the frame with the VHT PPDU format is notlimited to the data frame, but may be another type of frame such as amanagement frame.

In addition, the data frame may be transmitted toward the plurality ofSTAs 100-1 at one time. Specifically, the data frame is multiplexed. Forexample, the data frame is subjected to time division multiplexing, codedivision multiplexing, frequency division multiplexing, orthogonalfrequency division multiplexing, or space division multiplexing.Moreover, the data frame may be connected (aggregated).

Further, the frame with the VHT PPDU format will be described withreference to FIG. 9 . FIG. 9 is a diagram illustrating a configurationexample of the frame with the VHT PPDU format.

As illustrated in FIG. 9 , the frame with the VHT PPDU format includesfields such as Legacy-Short Training Field (L-STF), Legacy-Long TrainingField (L-LTF), Legacy-Signal Field (L-SIG), VHT-SIG-A, VHT-STF,VHT-SIG-B, and VHT-Data.

As illustrated in FIG. 9 , the VHT-SIG-A field includes fields such asBandwidth (BW), Space Time Block Coding (STBC), Group ID, NSTS/PartialAID, TXOP_PS_NOT_ALLOWED, Short Guard Interval (GI), Short GI N_(SYM)Disambiguation, Single User (SU)/MU(0) Coding, Low Density Parity Check(LDPC) Extra Orthogonal Frequency Division Multiplexing (OFDM) Symbol,SU VHT-Modulation and Coding Set (MCS)/MU (1-3) Coding, CyclicRedundancy Check (CRC), and Tail.

As illustrated in FIG. 9 , the NSTS/Partial AID field includes fieldssuch as SU NSTS and Partial AID in a case in which a communicationtarget is a single user, and includes fields such as MU(0) NSTS to MU(3)NSTS in a case in which the communication target is multiple users.Information decided on the basis of the AID is stored in the partial AIDfield in the related art, but information decided on the basis of thetentative AID is stored in the embodiment. For example, informationregarding a part of the tentative AID, for example, informationregarding a specific bit, is stored in the Partial AID field.

In addition, the STA 100-1 transmits a frame including the tentative AIDas transmission source information of the frame. Specifically, when adata transmission request to the AP 200-1 occurs, the control unit 120acquires the tentative AID associated with the AP 200-1 from the storageunit. Subsequently, the control unit 120 causes the data processing unit110 to generate a data frame. Then, the wireless communication unit 130transmits the frame with the VHT PPDU format on the basis of thegenerated data frame and the header including the acquired tentative AIDto the AP 200-1. For example, the wireless communication unit 130transmits the frame with the VHT PPDU format including the header inwhich the tentative AID is included in VHT SIG to the AP 200-1.

(B. Functional Details of AP)

Next, the functional details of the AP 200-1 will be described.

(B-1. Reception and Registration of Tentative AID)

The AP 200-1 receives a tentative AID notification frame including thetentative AID. Specifically, when the tentative AID notification frameis received from the STA 100-1, the data processing unit 210 acquiresthe information indicating the tentative AID included in the tentativeAID notification frame.

In addition, the AP 200-1 registers the acquired information indicatingthe tentative AID. Specifically, when the information indicating thetentative AID is acquired by the data processing unit 210, the controlunit 220 determines whether the tentative AID overlaps. When the controlunit 220 determines that the tentative AID does not overlap, the controlunit 220 causes the storage unit to store information indicating thetentative AID.

In addition, the AP 200-1 transmits a confirmation response frame forthe tentative AID notification frame on the basis of whether thetentative AID can be used. Specifically, in a case in which thetentative AID is registered, that is, the tentative AID does notoverlap, the control unit 220 causes the data processing unit 210 togenerate the confirmation response frame for the tentative AIDnotification frame including the information indicating the registeredtentative AID. Then, the generated confirmation response frame istransmitted to the STA 100-1 by the wireless communication unit 230.

(B-2. Sounding Process Using Tentative AID)

The AP 200-1 transmits a frame related to the channel informationrequest including the information related to the tentative AID dependingon a situation. Specifically, the AP 200-1 transmits a priornotification frame including the information indicating the tentativeAID. For example, when a data transmission request destined for the STA100-1 occurs, the control unit 220 acquires the tentative AID of the STA100-1 which is a destination. Subsequently, the control unit 220 causesthe data processing unit 210 to generate a VHT NDP Announcement frameincluding the information indicating the acquired tentative AID. Then,the generated VHT NDP Announcement frame is transmitted to the STA 100-1by the wireless communication unit 230.

Subsequently, the AP 200-1 transmits the channel information requestframe. For example, the control unit 220 causes the data processing unit210 to generate the NDP frame to collect channel information after apredetermined time has passed from the transmission of the priornotification frame. Then, the generated NDP frame is transmitted to theSTAs 100-1 by the wireless communication unit 230. Thereafter, the AP200-1 receives the channel information notification frame as a responseto the NDP frame from the STA 100-1. In addition, the AP 200-1 maycollect the channel information by individually transmitting anotherchannel information request frame different from the NDP frame to theSTAs 100-1. Specifically, after the VCB frame to the NDP frame isreceived, the control unit 220 causes the data processing unit 210 togenerate the BRP frame destined for the STA 100-1 having not receivingthe VCB frame. Then, the generated VCB frame is transmitted to the STA100-1 by the wireless communication unit 230.

In addition, the AP 200-1 receives the channel information notificationframe as a response to the channel information request frame. Forexample, when the VCB frame is received after the transmission of theNDP frame or the BRP frame, the data processing unit 210 acquires thechannel information included in the received VCB frame. Then, thecontrol unit 220 causes the storage unit to store the acquired channelinformation.

(B-3. Data Transmission and Reception Using Tentative AID)

The AP 200-1 transmits a frame including the tentative AID asdestination information of the frame. Specifically, when a datatransmission request to the STA 100-1 occurs, the control unit 220acquires the tentative AID associated with the STA 100-1. Subsequently,the control unit 220 causes the data processing unit 210 to generate adata frame including data desired to be delivered. Then, the wirelesscommunication unit 230 transmits the frame with the VHT PPDU format tothe STA 100-1 on the basis of the header including the acquiredtentative AID and the generated data frame.

In addition, the AP 200-1 receives the frame including the tentative AIDas transmission source information of the frame. Specifically, when theframe with the VHT PPDU format is received from the STA 100-1, thewireless communication unit 230 acquires the tentative AID included inthe header of the frame with the VHT PPDU format. Subsequently, thewireless communication unit 230 determines whether the acquiredtentative AID is the registered AID. When the wireless communicationunit 230 determines that the acquired tentative AID is the registeredAID, the wireless communication unit 230 receives the frame with the VHTPPDU format up to the tail of the frame and provides the data frameobtained in the reception to the data processing unit 110. Conversely,when the wireless communication unit 230 determines that the acquiredtentative AID is an unregistered tentative AID, the wirelesscommunication unit 230 may stop the frame reception process.

2-4. Process of Communication Device

Next, a process of the communication device 100-1 (200-1) according tothe embodiment will be described.

(Overview of Tentative AID Registration Process)

First, an overview of the tentative AID registration process in thecommunication device 100-1 (200-1) according to the embodiment will bedescribed with reference to FIG. 10 . FIG. 10 is a sequence diagramconceptually illustrating an overview of the tentative AID registrationprocess according to the embodiment. Moreover, the details of eachprocess will be described below.

The STA 100-1A sets tentative AID #1, for example, when a communicationrequest occurs (step S301).

Subsequently, the STA 100-1A transmits a Tentative AID Notify frame(tentative AID notification frame) including the set tentative AID #1 tothe AP 200-1 (step S302).

The AP 200-1 receiving the Tentative AID Notify frame transmits an ACKframe to the Tentative AID Notify frame to the STA 100-1A (step S303).

Subsequently, the AP 200-1 registers tentative AID #1 included in thereceived Tentative AID Notify frame (step S304).

Subsequently, the registration process such as the foregoing steps S301to S304 are executed in the STA 100-1B and the STA 100-1C (step S305 toS312).

Thereafter, the AP 200-1 transmits the VHT NDP Announcement frameincluding the registered tentative AID #1 to AID #3 in a case in whichcommunication with each STA 100 is executed (step S313). Moreover, thesounding process will be described below with reference to a sequencediagram and a flowchart.

(Details of Tentative AID Registration Process)

Next, the details of the tentative AID registration process in thecommunication device 100-1 (200-1) according to the embodiment will bedescribed with reference to FIG. 11 . FIG. 11 is a sequence diagramconceptually illustrating the details of the tentative AID registrationprocess according to the embodiment.

A management entity of the STA 100-1 sets tentative AID #1 (step S321).Specifically, when a data transmission request to the AP 200-1 occurs,the control unit 120 decides one tentative AID #1 of the self-device inregard to the AP 200-1 at random within the setting range of thetentative AID.

Subsequently, the management entity of the STA 100-1 instructs thewireless communication unit 130 to issue a notification of the tentativeAID (step S322). Specifically, when the tentative AID of the self-deviceis decided, the control unit 120 causes the data processing unit 110 togenerate the Tentative AID Notify frame including the informationindicating tentative AID #1.

Subsequently, the communication processing entity of the STA 100-1transmits the Tentative AID Notify frame to the AP 200-1 (step S323).Specifically, the wireless communication unit 130 transmits theTentative AID Notify frame generated by the data processing unit 110 tothe AP 200-1.

The communication processing entity of the AP 200-1 receiving theTentative AID Notify frame provides the management entity with tentativeAID #1 included in the received Tentative AID Notify frame (step S324).Specifically, when the Tentative AID Notify frame is received by thewireless communication unit 230, the data processing unit 210 acquiresthe information indicating tentative AID #1 included in the TentativeAID Notify frame. Then, the acquired information indicating tentativeAID #1 is provided to the control unit 220.

Subsequently, the management entity of the AP 200-1 registers theprovided tentative AID #1 (step S325). Specifically, the control unit220 causes the storage unit to store tentative AID #1 if tentative AID#1 indicated by the provided information does not overlap with thealready registered tentative AID.

Subsequently, the communication processing entity of the AP 200-1transmits an ACK frame to the received Tentative AID Notify frame to theSTA 100-1 (step S326). Specifically, the control unit 220 causes thedata processing unit 210 to generate the ACK frame to the Tentative AIDNotify frame. Then, the wireless communication unit 130 transmits thegenerated ACK frame to the STA 100-1.

(Overview of Sounding Process Using Tentative AID

Next, an overview of the sounding process using the tentative AID in thecommunication device 100-1 (200-1) according to the embodiment will bedescribed with reference to FIG. 12 . FIG. 12 is a sequence diagramconceptually illustrating the overview of the sounding process using thetentative AID according to the embodiment. Moreover, the details of eachprocess will be described below.

The AP 200-1 first transmits the VHT NDP Announcement frame includingtentative AID #1 to AID #3 to the STAs 100-1A to 100-1C (step S401).

Subsequently, the AP 200-1 transmits the NDP frame to the STAs 100-1A to100-1C (step S402) and the STA 100-1A receiving the NDP frame transmitsa VCB #1 frame to the AP 200-1 (step S403).

The AP 200-1 receiving the VCB #1 frame transmits a BRP #2 frame to theSTA 100-1B (step S404) and the STA 100-1B receiving the BRP #2 frametransmits a VCB #2 frame to the AP 200-1 (step S405).

The AP 200-1 receiving the VCB #2 frame transmits a BRP #3 frame to theSTA 100-1C (step S406) and the STA 100-1C receiving the BRP #3 frametransits a VCB #3 frame to the AP 200-1 (step S407).

The AP 200-1 receiving the VCB #3 frame transmits VHT MU Data #1 to VHTMU Data #3 subjected to space division multiplexing to the STAs 100-1Ato 100-1C (step S408).

(Details of Sounding Process Using Tentative AID

Next, the details of the sounding process using the tentative AID in thecommunication device 100-1 (200-1) according to the embodiment will bedescribed with reference to FIG. 13 . FIG. 13 is a sequence diagramconceptually illustrating the details of the sounding process using thetentative AID according to the embodiment.

The management entity of the AP 200-1 instructs the communicationprocessing entity to execute the sounding (step S401). Specifically,when a data transmission request to the STA 100-1 occurs, the controlunit 220 causes the data processing unit 210 to generate the VHT NDPAnnouncement frame including the information indicating the tentativeAID of the STA 100-1.

Subsequently, the communication processing entity of the AP 200-1transmits the VHT NDP Announcement frame to the STA 100-1 (step S402).Specifically, the wireless communication unit 230 transmits thegenerated VHT NDP Announcement frame to the STA 100-1. Moreover, the STA100-1 receiving the VHT NDP Announcement frame waits for transmission ofthe NDP frame in a case in which the VHT NDP Announcement frame includesthe information indicating the tentative AID of the self-device.

Subsequently, the communication processing entity of the AP 200-1transmits the NDP frame to the STA 100-1 (step S403). Specifically, thedata processing unit 210 generates the NDP frame after the VHT NDPAnnouncement frame is transmitted. Then, the wireless communication unit230 transmits the generated NDP frame to the STA 100-1.

The communication processing entity of the STA 100-1 receiving the NDPframe generates the channel information (step S404). Specifically, whenthe NDP frame is received, the wireless communication unit 130 executeschannel estimation on the basis the reception of the NDP. Then, thewireless communication unit 130 generates the channel information on thebasis of the channel estimation result.

Subsequently, the communication processing entity of the STA 100-1transmits the VCB frame to the AP 200-1 (step S405). Specifically, whenthe channel information is generated, the data processing unit 110generates the VCB frame including the channel information as a responseto the NDP frame. Then, the wireless communication unit 130 transmitsthe generated VCB frame to the AP 200-1.

The communication processing entity of the AP 200-1 receiving the VCBframe stores the channel information included in the VCB frame (stepS406). Specifically, when the VCB frame is received by the wirelesscommunication unit 230, the data processing unit 210 acquires thechannel information included in the VCB frame. Then, the acquiredchannel information is stored in the storage unit in association withthe tentative AID.

Subsequently, the management entity of the AP 200-1 instructs thecommunication processing entity to transmit data (step S407).Specifically, when the channel information is acquired from all of theSTAs 100-1 which are data transmission targets, the control unit 220causes the data processing unit 210 to generate the data frame includingthe data desired to be delivered. In addition, the control unit 220acquires the tentative AID of the STA 100-1 which is a destination ofthe data frame and notifies the wireless communication unit 230 of theacquired tentative AID.

The communication processing entity of the AP 200-1 receiving theinstruction to transmit the data transmits the VHT MU Data frame to theSTA 100-1 (step S408). Specifically, the wireless communication unit 230transmits the frames with the VHT PPDU format based on the plurality oftentative AIDs and the data frame to the plurality of STAs 100-1.Moreover, the frames with the VHT PPDU format can be subjected to thespace division multiplexing on the basis of the channel informationassociated with the tentative AID whose notification has been issued.

The communication processing entity of the STA 100-1 receiving the VHTMU Data frame provides the management entity of the received data (stepS409). Subsequently, in a case in which the information indicating thetentative AID of the header of the frame with the VHT PPDU formatincludes the tentative AID of the self-device, the wirelesscommunication unit 130 executes a process of receiving the data frame.Subsequently, the data frame obtained through the reception process isprovided to the data processing unit 110 and the data is acquired fromthe data frame by the data processing unit 110. Then, the acquired datais provided to the control unit 120 and the like.

(Registration Process Flow of Tentative AID in STA)

Next, the tentative AID registration process in the STA 100-1 accordingto the embodiment will be described with reference to FIG. 14 . FIG. 14is a flowchart conceptually illustrating the tentative AID registrationprocess in the STA 100-1 according to the embodiment.

The STA 100-1 determines whether the AP 200-1 is found (step S501).Specifically, the control unit 120 determines whether the AP 200-1 isfound on the basis of, for example, whether the beacon frame isreceived.

When the AP 200-1 is found, the STA 100-1 determines whether the VHTPPDU can be used (step S502). Specifically, when the AP 200-1 is found,the control unit 120 determines whether the VHT PPDU can be used incommunication with the AP 200-1.

When it is determined that the VHT PPDU can be used, the STA 100-1 setsthe tentative AID (step S503). Specifically, when the control unit 120determines that the VHT PPDU can be used, the control unit 120 decidesthe tentative AID unallocated to another STA 100-1 or the tentative AIDunset by another STA 100-1 as the tentative AID of the self-device.

Subsequently, the STA 100-1 generates the tentative AID notificationframe (step S504). Specifically, the control unit 120 causes the dataprocessing unit 110 to generate the tentative AID notification frameincluding the information indicating the decided tentative AID.

Subsequently, the STA 100-1 determines whether a wireless delivery pathcan be used (step S505). Specifically, the wireless communication unit130 determines whether the wireless delivery path is vacant by usingcarrier sensing or the like.

When it is determined that the wireless delivery path can be used, theSTA 100-1 transmits the generated frame to the AP 200-1 (step S506).Specifically, when it is determined that the wireless delivery path isthe vacant, the wireless communication unit 130 transmits the generatedtentative AID notification frame to the AP 200-1.

Subsequently, the STA 100-1 determines whether reception confirmation bythe ACK frame can be executed (step S507). Specifically, the controlunit 120 determines whether the reception confirmation by the ACK frameto the transmitted tentative AID notification frame is executed.

When it is determined that the reception confirmation by the ACK frameis not executed, the STA 100-1 registers the tentative AID (step S508).Specifically, when it is determined that the reception confirmation bythe ACK frame to the tentative AID notification frame is note executed,the control unit 120 causes the storage unit to store the tentative AIDof which the AP 200-1 is notified using the tentative AID notificationframe in association with the AP 200-1.

In addition, in a case in which it is determined in step S507 that thereception confirmation by the ACK frame is executed, the STA 100-1determines whether the ACK frame is received (step S509). Specifically,when it is determined that the reception confirmation by the ACK frameto the tentative AID notification frame is executed, the control unit120 waits for a predetermined time from the transmission of thetentative AID notification frame to the reception of the ACK frame.Moreover, when the ACK frame is received, the process proceeds to stepS508.

When it is determined that the ACK frame is not received, the STA 100-1determines whether the number of retransmissions of the tentative AIDnotification frame exceeds a predetermined number of times (step S510).Specifically, when it is determined that the ACK frame is not receiveduntil the predetermined time has passed from the transmission of thetentative AID notification frame, the control unit 120 determineswhether the number of retransmission of the tentative AID notificationframe exceeds a predetermined number of times.

When it is determined that the number of retransmissions of thetentative AID notification frame exceeds the predetermined number oftimes, the process ends. Otherwise, the process returns to step S503 andthe tentative AID may be reset.

(Flow of Tentative AID Registration Process in AP)

Next, the tentative AID registration process in the AP 200-1 accordingto the embodiment will be described with reference to FIG. 15 . FIG. 15is a flowchart conceptually illustrating the tentative AID registrationprocess in the AP 200-1 according to the embodiment.

The AP 200-1 determines whether the VHT PPDU can be used (step S601).Specifically, the control unit 220 determines whether the VHT PPDU canbe used in communication with the STA 100-1.

When it is determined that the VHT PPDU can be used, the AP 200-1 waitsfor the tentative notification frame (step S602). Specifically, thewireless communication unit 230 waits for the frame in a state in whichthe tentative AID notification frame can be received.

When the tentative AID notification frame is received, the AP 200-1determines whether the tentative AID overlaps (step S603). Specifically,when the tentative AID notification frame is received, the control unit220 determines whether the tentative AID indicated by the informationincluded in the tentative AID notification frame overlaps with thetentative AID already registered in regard to another STA 100-1.

When it is determined that the tentative AID does not overlap, the AP200-1 transmits the ACK frame to the STA 100-1 (step S604).Specifically, when it is determined that the tentative AID does notoverlap with the tentative AIDs of the other STAs 100-1, the controlunit 220 causes the data processing unit 210 to generate the ACK frameto the tentative AID notification frame. Then, the wirelesscommunication unit 230 transmits the generated ACK frame to the STA100-1.

Subsequently, the AP 200-1 acquires the MAC address (step S605).Specifically, the data processing unit 210 acquires the MAC address ofthe STA 100-1 which is a transmission source of the frame from thereceived tentative AID notification frame.

Subsequently, the AP 200-1 registers the tentative AID (step S606).Specifically, the control unit 220 causes the storage unit to store thetentative AID in association with the STA 100-1, that is, the MACaddress.

(Flow of Transmission and Reception Processes Using Tentative AID inSTA)

Next, transmission and reception processes using the tentative AID inthe STA 100-1 according to the embodiment will be described withreference to FIG. 16 . FIG. 16 is a flowchart conceptually illustratingthe transmission and reception processes using the tentative AID in anSTA 100-1 according to the embodiment. Moreover, the description ofsubstantially the same process as the above-described process will beomitted.

The STA 100-1 determines whether a data transmission request occurs(step S701). Specifically, when the data transmission request to the AP200-1 occurs, the control unit 120 determines whether the AP 200-1 is ina state in which the tentative AID is registered.

When the data transmission request occurs, the STA 100-1 acquires thedelivery data (step S702). Specifically, when it is determined that thetentative AID in regard to the AP 200-1 of a data transmission requestdestination is registered, the control unit 120 acquires data desired tobe delivered.

Subsequently, the STA 100-1 determines whether the VHT PPDU can be used(step S703). When it is determined that the VHT PPDU can be used, thetentative AID is acquired (step S704). Specifically, in a case in whichthe VHT PPDU can be used, the control unit 120 acquires the tentativeAID of the self-device in regard to the AP 200-1.

Subsequently, the STA 100-1 generates a value of the header of the VHTPPDU (step S705). Specifically, the control unit 120 generates the valuestored in the VHT SIG on the basis of the acquired tentative AID.

Subsequently, the STA 100-1 generates a frame with the VHT PPDU format(step S706). Specifically, the data processing unit 110 generates a dataframe including the acquired delivery data. Then, the wirelesscommunication unit 130 generates a frame with the VHT PPDU format on thebasis of the value stored in the VHT SIG and the generated data frame.Moreover, in a case in which it is determined in step S703 that the VHTPPDU is not used, a frame with a normal PPDU format may be generated.

Conversely, when it is determined in step S701 that the datatransmission request does not occur, the STA 100-1 determines whetherthe prior notification frame is received (step S707). Specifically, whenthe VHT NDP Announcement frame is received, the control unit 120determines whether the tentative AID of the self-device is included inthe information indicating the tentative AID of the frame.

When it is determined that the prior notification frame is received, theSTA 100-1 receives the NDP frame transmitted after the priornotification frame (step S708). Specifically, when the VHT NDPAnnouncement frame destined for the self-device is received, thewireless communication unit 130 waits for the NDP frame.

When the NDP frame is received, the STA 100-1 generates the channelinformation notification frame on the basis of the reception of the NDPframe (step S709). Specifically, when the NDP frame is received, thewireless communication unit 130 generates the channel information on thebasis of the reception of the NDP frame. Then, the control unit 120causes the data processing unit 110 to generate the VCB frame includingthe channel information generated on the basis of the reception of theNDP frame. Moreover, in a case in which the BRP frame destined for theself-device is received, the control unit 120 may cause the dataprocessing unit 110 to generate the VCB frame.

Subsequently, the STA 100-1 waits until a transmission timing comes(step S710). Specifically, the wireless communication unit 130 waits forthe transmission of the frame until the transmission timing of the VCBframe or the generated frame with the VHT PPDU format comes. Here, thetransmission timing of the VCB frame differs between a case in which theVCB frame is transmitted as a response to the NDP frame and a case inwhich the VCB frame is transmitted as a response to the BRP frame.

When the transmission timing comes, the STA 100-1 executes atransmission process (step S711). Specifically, when the transmissiontiming comes, the wireless communication unit 130 transmits the VCBframe or the frame with the VHT PPDU format.

Conversely, when it is determined in step S707 that the priornotification frame is not received, the STA 100-1 determines whether theframe with the VHT PPDU format is received (step S712). Specifically,the wireless communication unit 130 waits in a state in which the framewith the VHT PPDU format can be received.

When it is determined that the frame with the VHT PPDU format isreceived, the STA 100-1 decodes the header of the frame (step S713).Specifically, when the VHT PPDU is received, the wireless communicationunit 130 decodes the VHT SIG of the frame with the VHT PPDU format.

Subsequently, the STA 100-1 acquires the tentative AID of theself-device (step S714). Specifically, the wireless communication unit130 acquires the tentative AID of the self-device from the storage unit.

Subsequently, the STA 100-1 determines whether the tentative AID of theself-device is included in the header (step S715). Specifically, thewireless communication unit 130 determines whether the acquiredtentative AID is included in the decoded VHT SIG. Moreover, informationgenerated from the tentative AID may be used instead of the tentativeAID.

When it is determined that the tentative AID of the self-device isincluded in the header, the STA 100-1 sets a reception parameter (stepS716). Specifically, when it is determined that the tentative AID of theself-device is included in the header, the wireless communication unit130 sets the reception parameter of the self-device on the basis ofinformation used to receive a portion subsequent to the header andincluded in the header.

Subsequently, the STA 100-1 decodes the data portion (step S717).Specifically, the wireless communication unit 130 decodes the dataportion located after the header.

Subsequently, the STA 100-1 determines whether the data portion issuccessfully received (step S718). Specifically, the data processingunit 110 determines whether the data portion is successfully received.

When it is determined that the frame is successfully received, the STA100-1 determines whether the ACK frame is requested (step S719). When itis determined that the ACK frame is requested, the ACK frame istransmitted to the AP 200-1 (step S720).

(Flow of Transmission and Reception Processes Using Tentative AID in AP)

Next, transmission and reception processes using the tentative AID inthe AP 200-1 according to the embodiment will be described withreference to FIG. 17 . FIG. 17 is a flowchart conceptually illustratingthe transmission and reception processes using the tentative AID in theAP 200-1 according to the embodiment. Moreover, the description ofsubstantially the same process as the above-described process will beomitted.

The AP 200-1 determines whether a data transmission request occurs (stepS801). Specifically, the control unit 220 determines whether there isdata desired to be delivered. For example, the control unit 220determines that there is the data in a transmission buffer.

When it is determined that the data transmission request occurs, the AP200-1 determines whether multiplexing communication is used (step S802).Specifically, when it is determined that there is the data desired to bedelivered, the control unit 220 determines whether the multiplexingcommunication is used to deliver the data in a case in which there arethe plurality of pieces of data.

When it is determined that the multiplexing communication is used, theAP 200-1 determines whether the tentative AID of the STA 100-1 which isa destination is registered (step S803). Specifically, when it isdetermined that the multiplexing communication is used to deliver thedata, the control unit 220 determines whether the tentative AID of theSTA 100-1 which is a delivery destination of the data is registered.

When it is determined that the tentative AID of the STA 100-1 which isthe destination is registered, the AP 200-1 acquires the tentative AIDof the STA 100-1 (step S804). Specifically, when it is determined thatthe tentative AID of the STA 100-1 which is the delivery destination ofthe data is registered, the control unit 220 acquires the tentative AIDfrom the storage unit.

Subsequently, the AP 200-1 sets a destination of the prior notificationframe (step S805). Specifically, the control unit 220 sets the acquiredtentative AID as destination information of the VHT NDP Announcementframe. Then, the data processing unit 210 stores information indicatingthe set tentative AID in a field of the destination information.

Then, the AP 200-1 repeats the processes of the foregoing steps S803 toS805 until the setting of the destination is completed in all the STAs100-1 which are destinations (step S806).

When the setting of the destination is completed in all the STAs 100-1which are destinations, the AP 200-1 determines whether the wirelessdelivery path can be used (step S807). When it is determined that thewireless delivery path can be used, the prior notification frame istransmitted (step S808). Specifically, when it is determined that thewireless delivery path is vacant, the wireless communication unit 230transmits the generated VHT NDP Announcement frame to the STA 100-1.

Subsequently, the AP 200-1 transmits the NDP frame (step S809).Specifically, the wireless communication unit 230 transmits the NDPframe to the STA 100-1 after a predetermined time has passed from thetransmission of the VHT NDP Announcement frame.

Subsequently, the AP 200-1 determines whether the channel informationnotification frame is received (step S810). Specifically, the wirelesscommunication unit 230 waits in a receivable state until the VCB frameis received after the reception of the NDP frame.

When the channel information notification frame is received, the AP200-1 acquires the channel information (step S811). Specifically, whenthe VCB frame is received, the data processing unit 210 acquires thechannel information from the VCB frame.

Subsequently, the AP 200-1 determines whether collection of the channelinformation is completed (step S812). Specifically, the control unit 220determines whether the VCB frames are successfully received from all theSTAs 100-1 which are the destination of the VHT NDP Announcement frame.Moreover, the STA 100-1 having not received the VCB frame may berequested to transmit the VCB frame by transmission of the BRP frame.

When it is determined that the collection of the channel information iscompleted, the AP 200-1 sets a transmission parameter (step S813).Specifically, when it is determined that the VCB frames are receivedfrom all the STAs 100-1, the control unit 220 causes the wirelesscommunication unit 230 to set the transmission parameter formultiplexing communication on the basis of the channel informationacquired via the VCB frame.

Subsequently, the AP 200-1 generates a data frame (step S814).Specifically, the control unit 220 causes the data processing unit 110to generate the data frame destined for the STA 100-1.

The AP 200-1 repeats the processes of the foregoing steps S813 and S814until the setting of all the destinations is completed (step S815).

When the setting of all the destinations is completed, the AP 200-1generates a header (step S816). Specifically, the wireless communicationunit 230 generates the VHT SIG including the tentative AID asdestination information. Moreover, in a case in which multiplexingcommunication is used, the wireless communication unit 230 generates amultiple-user VHT SIG. In a case in which no multiplexing communicationis used, the wireless communication unit 230 generates a single user VHTSIG.

Subsequently, the AP 200-1 determines whether the wireless delivery pathcan be used (step S817). When it is determined that the wirelessdelivery path can be used, the frame with the VHT PPDU format istransmitted (step S818). Specifically, when it is determined that thewireless delivery path is vacant, the wireless communication unit 230transmits the frame with the VHT PPDU format including the generatedframe and the VHT SIG to the STA 100-1.

Moreover, when it is determined in step S802 that no multiplexingcommunication is used, the AP 200-1 acquires the parameter of theself-device (step S819). Specifically, the control unit 220 acquires theparameter of the self-device used to construct the frame and the framewith the VHT PPDU format.

Subsequently, the AP 200-1 generates the data frame (step S820).Specifically, the control unit 220 causes the data processing unit 210to generate the data frame on the basis of the acquired parameter. Then,the process proceeds to step S816 and the frame with the VHT PPDU formatincluding the data frame is transmitted.

2-5. Conclusion of First Embodiment

In this way, according to the first embodiment of the presentdisclosure, the STA 100-1 transmits the first frame including the secondassociation identifier decided by a communication device to which afirst association identifier is allocated and receives the second frameincluding information related to the second association identifier. Inaddition, the AP 200-1 receives the first frame including the secondassociation identifier generated by a communication device to which thefirst association identifier is allocated and transmits the second frameincluding the information related to the second association identifier.Therefore, by using the tentative AID in communication between the STA100-1 and the AP 200-1, it is possible to improve communicationefficiency in communication before the AID is allocated. For example, byusing the tentative AID instead of the MAC address, it is possible toreduce the size of the header without executing the association process.In addition, by omitting the association process, it is possible toreduce an overhead of communication with the AP 200-1.

In addition, the second association identifier is decided within asetting range of the second association identifier. Therefore, byselecting the tentative AID within the range of a pre-decided value, itis possible to execute management of the tentative AID and a processusing the tentative AID more efficiently than in a case in which thetentative AID is decided under no rule in the STA 100-1.

In addition, the setting range of the second association identifierincludes a setting range different from the setting range of the firstassociation identifier. Therefore, by ensuring the tentative AIDseparately from the AID, it is possible to operate the tentative AIDwithout having an influence on the AID. Further, in a case in which thenumber of STAs 100-1 desiring connection (association) with the AP 200-1is greater than the number of ensured AIDs, it is difficult for some ofthe STAs 100-1 to be connected to the AP 200-1. In this case, in therelated art, an improvement in the situation is achieved in many casesby increasing the number of APs 200-1. However, in the configuration,even in a case in which the AIDs are depleted, the STAs 100-1 can beconnected to the AP 200-1 without increasing the number of APs 200-1.Accordingly, it is possible to increase communication opportunities ofthe STAs 100-1.

In addition, on the other hand, the setting range of the secondassociation identifier may also include the setting range of the firstassociation identifier. In this case, it is possible to executecommunication using the tentative AID without newly ensuring the settingrange of the tentative AID.

In addition, the STA 100-1 decides the second association identifierdifferent from the second association identifier used in anothercommunication device. Therefore, by selecting the tentative AID notoverlapping with the tentative AIDs of the other STAs 100-1 in advance,it is possible to suppress unnecessary occurrence of communication dueto the overlapping of the tentative AID. For example, it is possible toprevent notification of the tentative AID from being executed again dueto the overlapping of the tentative AID from being found in the AP200-1. Accordingly, it is possible to suppress deterioration incommunication efficiency of the tentative AID registration process.

In addition, information related to the second association identifierincludes information indicating the second association identifier.Therefore, it is possible to ascertain the tentative AID withoutexecuting a special process. In addition, the information related to thesecond association identifier may also include information decided onthe basis of the second association identifier. In this case, it ispossible to ascertain the tentative AID with information less than thetentative AID. Accordingly, in a case in which the tentative AID isincluded as destination information in the header, it is possible tofurther reduce the size of the header.

In addition, the second frame includes a frame related to a channelinformation request. Therefore, it is possible to improve efficiency ofcommunication related to the sounding process of collecting the channelinformation.

In addition, the frame related to the channel information requestincludes a frame for issuing a notification of transmission of a channelrequest frame. Therefore, the prior notification frame using the AID ofthe related art can be used before allocation of the AID. Accordingly,since the channel information can be collected before the allocation ofthe AID, the channel information can be used for multiplexingcommunication or the like. As a result, it is possible to improvecommunication efficiency. Moreover, the second frame may include thechannel information request frame. For example, the tentative AID may beused instead of the reception address of the BRP frame. In this case, byshortening the size of the frame than the size of the BRP frame of therelated art, it is possible to improve communication efficiency of theBRP frame.

In addition, the first frame includes a frame including the secondassociation identifier as transmission source information of the frame.Therefore, by using the tentative AID instead of a transmission sourceaddress, it is possible to reduce the size of the frame. Accordingly, itis possible to improve communication efficiency in communication of theframe.

In addition, the second frame includes a frame including the secondassociation identifier as destination information of the frame.Therefore, by using the tentative AID instead of a destination address,it is possible to reduce the size of the frame. Accordingly, it ispossible to improve communication efficiency in communication of theframe.

In addition, the STA 100-1 transmits the first frame including thesecond association identifier different from the second associationidentifier included in the first frame for which a confirmation responseframe has not been received. Therefore, in a case in which the tentativeAID of which the AP 200-1 is notified using the tentative AIDnotification frame is not registered in the AP 200-1 because ofoverlapping of the tentative AID or the like, it is possible to preventthe tentative AID from remaining unregistered by transmitting thetentative AID notification frame including a tentative AID differentfrom the tentative AID. Accordingly, it is possible to improvereliability of the registration of the tentative AID.

In addition, the AP 200-1 transmits a confirmation response frame forthe first frame on the basis of whether the second associationidentifier is usable. Therefore, by presenting the usability of thetentative AID to the STA 100-1 in accordance with whether theconfirmation response frame is transmitted, it is possible to suppressan operation related to unnecessary communication of the STA 100-1. Forexample, it is possible to suppress retransmission of the tentative AIDnotification frame despite failure of reception of the tentative AIDnotification frame, waiting of communication using the tentative AID byregistering the tentative AID, and the like. Accordingly, it is possibleto suppress an increase in a communication amount or a communicationoverhead.

In addition, whether the second association identifier is usable isdetermined on the basis of whether the second association identifieroverlaps between communication devices transmitting the first frame.Therefore, by preventing the overlapping of the tentative AID, it ispossible to prevent occurrence of disorder of the communication in whichthe tentative AID is used.

In addition, the second frame is transmitted to a plurality ofcommunication devices at one time. Therefore, it is possible to furtherimprove communication efficiency, compared to a case in which, forexample, the frame with the VHT PPDU format is individually transmittedto the plurality of STAs 100-1.

In addition, the second frame is multiplexed. Therefore, it is possibleto improve use efficiency of communication resources such as a time, afrequency, a space, or the like. Accordingly, it is possible to improvecommunication efficiency of the communication in which the tentative AIDis used.

3. Second Embodiment (Association Process Using Tentative AID)

The communication device 100-1 (200-1) according to the first embodimentof the present disclosure has been described above. Next, acommunication device 100-2 (200-2) according to a second embodiment ofthe present disclosure will be described. A communication systemaccording to the embodiment performs an association process using atentative AID. Moreover, the basic configuration of the communicationdevice 100-2 (200-2) according to the embodiment is substantially thesame as the configuration according to the first embodiment, andtherefore the description thereof will be omitted.

3-1. Functional Details of Communication Device

First, the functional details of the communication device 100-2 (200-2)according to the embodiment of the present disclosure will be described.

(A. Functional Details of STA)

First, the functional details of the STA 100-2 will be described.

(A-5. Association Request Process)

The STA 100-2 transmits the association request frame including thetentative AID as the first frame. Specifically, the control unit 120decides the tentative AID in a case in which connection with the AP200-2 is established. Subsequently, the control unit 120 causes the dataprocessing unit 110 to generate an association request frame includingthe decided tentative AID. Then, the wireless communication unit 130transmits the generated association request frame to the AP 200-2.Moreover, the tentative AID can be obtained as the 24th informationcomponent of the association request frame defined in the IEEE 802.11standard.

(A-6. Association Response Process)

The STA 100-2 receives the association response frame includinginformation related to the tentative AID as the second frame.Specifically, when the association response frame for the associationrequest frame is received, the STA 100-2 determines whether theassociation response frame is an association response frame destined forthe self-device on the basis of the information related to the tentativeAID included in the association response frame. In a case in which it isdetermined that the association response frame is the associationresponse frame destined for the self-device, the STA 100-2 registers theAID included in the association response frame as the AID of theself-device. Moreover, the association response frame is multiplexed.

For example, the wireless communication unit 130 determines whether thetentative AID of the self-device is included in the informationindicating the tentative AID included in the received header. In a casein which the tentative AID of the self-device is included in the header,the wireless communication unit 130 decodes the frame and provides aframe obtained through the decoding to the data processing unit 110.Subsequently, the data processing unit 110 acquires informationindicating the AID from the provided association response frame. Then,the control unit 120 registers the AID indicated by the acquiredinformation as the AID of the self-device. Moreover, the associationresponse frame may be a frame obtained by aggregating the plurality ofassociation response frames.

(B. Functional Details of AP)

Next, the functional details of the AP 200-2 will be described.

(B-4. Association Request Process)

The AP 200-2 receives an association request from including thetentative AID as the first frame. Specifically, when the associationrequest frame is received, the data processing unit 210 acquires thetentative AID included in the association request frame. Subsequently,the control unit 220 decides the AID for the STA 100-2 which is atransmission source of the association request frame. Then, the controlunit 220 causes the storage unit to store the decided AID and theacquired tentative AID in association therewith.

(B-5. Association Response Process)

The AP 200-2 transmits an association response frame including theinformation related to the tentative AID as the second frame.Specifically, in a case in which the plurality of association requestframes are received within a predetermined time, the STA 200-2 transmitsthe association response frames for the association request frames atone time.

For example, the control unit 220 acquires the AID decided on the basisof an association request and the tentative AID association with theAID. Subsequently, the control unit 220 causes the data processing unit210 to generate an association response frame including the acquired AIDand the tentative AID. Then, the process of generating the associationresponse frame is repeated by the number of transmission sources of theassociation request frame. Subsequently, the wireless communication unit230 executes a process of multiplexing each of the generated associationresponse frames and the multiplexed association response frames aretransmitted to the STA 100-2 which is a destination.

3-2. Process of Communication Device

Next, a process of the communication device 100-2 (200-2) according tothe embodiment will be described.

(Overview of Association Process Using Tentative AID)

First, an overview of the association process using the tentative AID inthe communication device 100-2 (200-2) according to the embodiment willbe described with reference to FIG. 18 . FIG. 18 is a sequence diagramconceptually illustrating an overview of the association process usingthe tentative AID according to the embodiment.

When a connection request with the AP 200-2 occurs, the STA 100-2A setstentative ADI #1 at random (step S351).

Subsequently, the STA 100-2A transmits the association request frameincluding the set tentative AID #1 to the AP 200-2 (step S352).

The AP 200-2 receiving the association request frame transmits the ACKframe to the Association Request frame to the STA 100-2A (step S353).Moreover, when the ACK frame is received, the STA 100-2A registerstentative ADI #1.

Subsequently, the AP 200-2 sets AID #1 in the STA 100-2A (step S354).Moreover, the AP 200-2 registers tentative AID #1 included in thereceived association request frame.

Subsequently, the association request process such as the foregoingsteps S351 to S354 is executed in the STAs 100-2B and 100-2C (steps S355to S362).

Thereafter, the AP 200-2 multiplexes association response frames #1 to#3 including the set AIDs #1 to #3 and the registered tentative AIDs #1to #3 and transmits the multiplexed frames (step S363).

The STAs 100-2A to 100-2C receiving the frames in which associationresponse frames #1 to #3 are multiplexed register AID #1 to AID #3allocated to the self-device included in the multiplexed frames,respectively (steps S364 to S366). Specifically, the STAs 100-2A to100-2C decode the frames destined for the self-devices on the basis ofthe tentative AID of the self-devices and acquire the AIDs allocated tothe self-devices.

(Flow of Association Process Using Tentative AID in STA)

Next, a flow of the association process using the tentative AID in theSTA 100-2 according to the embodiment will be described with referenceto FIG. 19 . FIG. 19 is a flowchart conceptually illustrating atentative AID registration process and an association process in the STA100-2 according to the embodiment.

Processes of steps S501 to S503 are substantially the same as theprocesses described with reference to FIG. 14 , and therefore thedescription thereof will be omitted.

The STA 100-2 determines whether connection with the AP 200-2 is made(step S551). Specifically, the control unit 120 determines whether theconnection with the AP 200-2 is established, that is, the associationprocess is executed.

In a case in which it is determined that the connection with the AP200-2 is desired, the STA 100-2 generates the association request frameincluding the tentative AID (step S552). Specifically, when it isdetermined that the connection with the AP 200-2 is established, thecontrol unit 120 causes the data processing unit 110 to generate theassociation request frame including the decided tentative AID. Moreover,in a case in which it is determined that the connection with the AP200-2 is not established, the control unit 120 causes the dataprocessing unit 110 to generate the tentative AID notification frame asin the first embodiment.

Subsequently, the process proceeds to step S505. The subsequentprocesses are substantially the same as the processes described withreference to FIG. 14 , and therefore the description thereof will beomitted.

(Flow of Association Process Using Tentative AID in AP)

Next, an association process using the tentative AID in the AP 200-2according to the embodiment will be described with reference to FIG. 20. FIG. 20 is a flowchart conceptually illustrating a tentative AIDregistration process and an association process in the AP 200-2according to the embodiment.

The processes of steps S601 to S606 are substantially the same as theprocesses described with reference to FIG. 15 , and therefore thedescription thereof will be omitted.

When it is determined in step S602 that the tentative AID notificationframe is not received, the AP 200-2 determines whether the associationrequest frame including the tentative AID is received (step S651).Specifically, the data processing unit 210 determines whether thereceived frame is the association request frame.

When it is determined that the association request frame including thetentative AID is received, the AP 200-2 determines whether theconnection is permitted to the transmission source of the frame (stepS652). Specifically, the control unit 220 determines whether theconnection with the STA 100-2 which is the transmission source of theassociation request frame is established.

In a case in which it is determined that the connection with thetransmission source of the association request frame including thetentative AID is permitted, the AP 200-2 sets the AID (step S653).Specifically, when it is determined that the connection with the STA100-2 is established, the control unit 220 sets the AID in the STA100-2.

Subsequently, the AP 200-2 generates the association response frame(step S654). Specifically, the control unit 220 causes the dataprocessing unit 210 to generate the association response frame includingthe set AID and the tentative AID. Then, the plurality of generatedassociation response frames are multiplexed and the multiplexed frame istransmitted to the STA 100-2.

3-3. Conclusion of Second Embodiment

In this way, according to the second embodiment of the presentdisclosure, the first frame includes the association request frame andthe second frame includes the association response frame for theassociation request frame. Therefore, for example, by using thetentative AID whose notification is issued using the association requestframe in a process of demultiplexing the multiplexed frame, it ispossible to multiplex the association response frame. Accordingly,communication resources related to the transmission of the associationresponse frame are efficiently used, and thus it is possible to improveefficiency of communication related to the association process.

4. Application Examples

The technology according to the present disclosure is applicable tovarious products. For example, the STA 100 may be implemented as amobile terminal such as smartphones, tablet personal computers (PCs),notebook PCs, portable game terminals, or digital cameras, a fixed-typeterminal such as television receivers, printers, digital scanners, ornetwork storages, or a car-mounted terminal such as car navigationdevices. In addition, the STA 100 may be implemented as a terminal (alsoreferred to as machine type communication (MTC) terminal) which performsmachine-to-machine (M2M) communication, such as smart meters, vendingmachines, remote monitoring devices, or point of sale (POS) terminals.Furthermore, the STA 100 may be a wireless communication module mountedin such terminals (e.g., integrated circuit modules including one die).

On the other hand, for example, the AP 200 may be implemented as awireless LAN access point (also referred to as a wireless base station)having or not having a router function. In addition, the AP 200 may beimplemented as a mobile wireless LAN router. Furthermore, the AP 200 maybe a wireless communication module (e.g., integrated circuit modulesincluding one die) mounted on these devices.

4-1. First Application Example

FIG. 21 is a block diagram illustrating an example of a schematicconfiguration of a smartphone 900 to which the technology according tothe present disclosure can be applied. The smartphone 900 includes aprocessor 901, a memory 902, a storage 903, an external connectioninterface 904, a camera 906, a sensor 907, a microphone 908, an inputdevice 909, a display device 910, a speaker 911, a wirelesscommunication interface 913, an antenna switch 914, an antenna 915, abus 917, a battery 918, and an auxiliary controller 919.

The processor 901 may be, for example, a central processing unit (CPU)or a system on chip (SoC), and controls functions of an applicationlayer and other layers of the smartphone 900. The memory 902 includes arandom access memory (RAM) and a read only memory (ROM), and storesprograms executed by the processor 901 and data. The storage 903 caninclude a storage medium such as a semiconductor memory or a hard disk.The external connection interface 904 is an interface for connecting anexternally attached device such as a memory card or a universal serialbus (USB) device to the smartphone 900.

The camera 906 includes, for example, an image sensor such as a chargecoupled device (CCD) or a complementary metal oxide semiconductor(CMOS), and generates a captured image. The sensor 907 can include asensor group including, for example, a positioning sensor, a gyrosensor, a geomagnetic sensor, an acceleration sensor, and the like. Themicrophone 908 converts voice input to the smartphone 900 into an audiosignal. The input device 909 includes, for example, a touch sensor thatdetects touches on a screen of the display device 910, a key pad, akeyboard, buttons, switches, and the like, and accepts an operation orinformation input from a user. The display device 910 includes a screensuch as a liquid crystal display (LCD) or an organic light emittingdiode (OLED) display, and displays an output image of the smartphone900. The speaker 911 converts an audio signal output from the smartphone900 into voice.

The wireless communication interface 913 supports one or more ofwireless LAN standards such as IEEE 802.11a, 11b, 11g, 11n, 11ac, and11ad, and executes wireless LAN communication. The wirelesscommunication interface 913 can communicate with other devices via awireless LAN access point in an infrastructure mode. In addition, thewireless communication interface 913 can directly communicate with otherdevices in a direct communication mode such as an ad hoc mode, or Wi-FiDirect (registered trademark). Note that, in Wi-Fi Direct mode, unlikethe ad hoc mode, one of two terminals operates as an access point, butcommunication is performed directly between the terminals. The wirelesscommunication interface 913 can typically include a baseband processor,a radio frequency (RF) circuit, a power amplifier, and the like. Thewireless communication interface 913 may be a single-chip module onwhich a memory for storing a communication control program, a processorfor executing the program, and a relevant circuit are integrated. Thewireless communication interface 913 may support other types of wirelesscommunication schemes such as a short-range wireless communicationscheme, a close proximity wireless communication scheme, or a cellularcommunication scheme, in addition to the wireless LAN scheme. Theantenna switch 914 switches a connection destination of the antenna 915among a plurality of circuits (e.g., circuits for different wirelesscommunication schemes) included in the wireless communication interface913. The antenna 915 includes a single antenna element or a plurality ofantenna elements (e.g., a plurality of antenna elements included in aMIMO antenna), and is used for transmission and reception of a wirelesssignal through the wireless communication interface 913.

Note that the configuration of the smartphone 900 is not limited to theexample of FIG. 21 , and the smartphone 900 may include a plurality ofantennas (e.g., an antenna for a wireless LAN and an antenna for a closeproximity wireless communication scheme). In this case, the antennaswitch 914 may be omitted from the configuration of the smartphone 900.

The bus 917 connects the processor 901, the memory 902, the storage 903,the external connection interface 904, the camera 906, the sensor 907,the microphone 908, the input device 909, the display device 910, thespeaker 911, the wireless communication interface 913, and the auxiliarycontroller 919 to one another. The battery 918 supplies electric powerto each of the blocks of the smartphone 900 illustrated in FIG. 21 via apower supply line partially indicated by dashed lines in the figure. Theauxiliary controller 919 causes the required minimum functions of thesmartphone 900 to operate, for example, in the sleep mode.

In the smartphone 900 illustrated in FIG. 21 , the data processing unit110, the control unit 120, and the wireless communication unit 130described with reference to FIG. 3 may be mounted on the wirelesscommunication interface 913. In addition, at least some of thesefunctions may be mounted on the processor 901 or the auxiliarycontroller 919. For example, the control unit 120 decides the tentativeAID and the frame with the VHT PPDU format in which the decidedtentative AID is transmission source information is generated by thedata processing unit 110. Then, the generated frame is transmitted bythe wireless communication unit 130. Therefore, by using the tentativeAID in the communication between the smartphone 900 and the accesspoint, it is possible to improve efficiency of communication between thesmartphone 900 and the access point.

Note that the smartphone 900 may operate as a wireless access point(software AP) by the processor 901 executing an access point function atthe application level. In addition, the wireless communication interface913 may have the wireless access point function.

4-2. Second Application Example

FIG. 22 is a block diagram illustrating an example of a schematicconfiguration of a car navigation device 920 to which the technologyaccording to the present disclosure can be applied. The car navigationdevice 920 includes a processor 921, a memory 922, a global positioningsystem (GPS) module 924, a sensor 925, a data interface 926, a contentplayer 927, a storage medium interface 928, an input device 929, adisplay device 930, a speaker 931, a wireless communication interface933, an antenna switch 934, an antenna 935, and a battery 938.

The processor 921 may be, for example, a CPU or SoC, and controls anavigation function and other functions of the car navigation device920. The memory 922 includes a RAM and a ROM, and stores programsexecuted by the processor 921 and data.

The GPS module 924 measures the position (e.g., latitude, longitude, andaltitude) of the car navigation device 920 using GPS signals receivedfrom a GPS satellite. The sensor 925 can include a sensor groupincluding, for example, a gyro sensor, a geomagnetic sensor, and abarometric sensor. The data interface 926 is connected to, for example,an in-vehicle network 941 via a terminal that is not illustrated, andacquires data generated on the vehicle side such as car speed data.

The content player 927 reproduces the content stored in a storage medium(e.g., CD or DVD) inserted into the storage medium interface 928. Theinput device 929 includes, for example, a touch sensor that detectstouches on a screen of the display device 930, buttons, switches, andthe like, and accepts an operation or information input from the user.The display device 930 includes a screen such as an LCD or an OLEDdisplay, and displays a navigation function or an image of content to bereproduced. The speaker 931 outputs sound of the navigation function orthe content to be reproduced.

The wireless communication interface 933 supports one or more ofwireless LAN standards such as IEEE 802.11a, 11b, 11g, 11n, 11ac, and11ad, and executes wireless LAN communication. The wirelesscommunication interface 933 can communicate with other devices via awireless LAN access point in an infrastructure mode. In addition, thewireless communication interface 933 can directly communicate with otherdevices in a direct communication mode, such as an ad hoc mode and Wi-FiDirect. The wireless communication interface 933 can typically include abaseband processor, an RF circuit, a power amplifier, and the like. Thewireless communication interface 933 may be a single-chip module onwhich a memory for storing a communication control program, a processorfor executing the program, and a relevant circuit are integrated. Thewireless communication interface 933 may support other types of wirelesscommunication schemes such as a short-range wireless communicationscheme, a close proximity wireless communication scheme, or a cellularcommunication scheme, in addition to the wireless LAN scheme. Theantenna switch 934 switches a connection destination of the antenna 935among a plurality of circuits included in the wireless communicationinterface 933. The antenna 935 includes a single antenna element or aplurality of antenna elements, and is used for transmission andreception of a wireless signal through the wireless communicationinterface 933.

Note that the configuration of the car navigation device 920 is notlimited to the example of FIG. 22 , and the car navigation device 920may include a plurality of antennas. In this case, the antenna switch934 may be omitted from the configuration of the car navigation device920.

The battery 938 supplies electric power to each of the blocks of the carnavigation device 920 illustrated in FIG. 22 via a power supply linepartially indicated by a dashed line in the figure. In addition, thebattery 938 accumulates electric power supplied from the vehicle side.

In the car navigation device 920 illustrated in FIG. 22 , the dataprocessing unit 110, the control unit 120, and the wirelesscommunication unit 130 described with reference to FIG. 3 may be mountedon the wireless communication interface 933. In addition, at least someof these functions may be mounted on the processor 921. For example, thecontrol unit 120 decides the tentative AID and the frame with the VHTPPDU format in which the decided tentative AID is transmission sourceinformation is generated by the data processing unit 110. Then, thegenerated frame is transmitted by the wireless communication unit 130.Accordingly, by using the tentative AID as transmission sourceinformation in the communication between the car navigation device 920and the access point, it is possible to improve efficiency ofcommunication between the car navigation device 920 and the accesspoint.

In addition, the wireless communication interface 933 may operate as theabove-described AP 200 and may provide wireless connection to a terminalcarried by a user getting in a vehicle. At this time, for example, thewireless communication unit 230 receives the frame including thetentative AID and the control unit 220 causes the data processing unit210 to generate the frame with the VHT PPDU format in which thetentative AID included in the received frame is destination information.Then, the generated frame is transmitted by the wireless communicationunit 230. Therefore, by using the tentative AID in the communicationbetween the car navigation device 920 and a terminal carried by theuser, it is possible to improve efficiency of communication between thenavigation device 920 and the terminal.

Further, the technology according to the present disclosure may beimplemented as an in-vehicle system (or vehicle) 940 including one ormore blocks of the above-described car navigation device 920, thein-vehicle network 941, and a vehicle-side module 942. The vehicle-sidemodule 942 generates vehicle-side data such as vehicle speed, enginerpm, or failure information, and outputs the generated data to thein-vehicle network 941.

4-3. Third Application Example

FIG. 23 is a block diagram illustrating an example of a schematicconfiguration of a wireless access point 950 to which the technologyaccording to the present disclosure can be applied. The wireless accesspoint 950 includes a controller 951, a memory 952, an input device 954,a display device 955, a network interface 957, a wireless communicationinterface 963, an antenna switch 964, and an antenna 965.

The controller 951 may be, for example, a CPU or a digital signalprocessor (DSP), and causes various functions (e.g., access restriction,routing, encryption, firewall, log management, and the like) of theInternet Protocol (IP) layer and higher layers of the wireless accesspoint 950 to be operated. The memory 952 includes a RAM and a ROM, andstores a program to be executed by the controller 951 and various kindsof control data (e.g., a terminal list, a routing table, an encryptionkey, security settings, a log, and the like).

The input device 954 includes, for example, a button, a switch, or thelike and accepts an operation from a user. The display device 955includes an LED lamp or the like, and displays operation status of thewireless access point 950.

The network interface 957 is a wired communication interface for thewireless access point 950 to connect to a wired communication network958. The network interface 957 may include a plurality of connectionterminals. The wired communication network 958 may be a LAN such asEthernet (registered trademark) or a wide area network (WAN).

The wireless communication interface 963 supports one or more ofwireless LAN standards such as IEEE 802.11a, 11b, 11g, 11n, 11ac, and11ad, and provides wireless connection to a neighboring terminal as anaccess point. The wireless communication interface 963 can typicallyinclude a baseband processor, an RF circuit, a power amplifier, and thelike. The wireless communication interface 963 may be a single-chipmodule on which a memory for storing a communication control program, aprocessor for executing the program, and a relevant circuit areintegrated. The antenna switch 964 switches a connection destination ofthe antenna 965 among a plurality of circuits included in the wirelesscommunication interface 963. The antenna 965 includes a single antennaelement or a plurality of antenna elements, and is used for transmissionand reception of a wireless signal through the wireless communicationinterface 963.

In the wireless access point 950 illustrated in FIG. 23 , the dataprocessing unit 210, the control unit 220, and the wirelesscommunication unit 230 described with reference to FIG. 3 may be mountedon the wireless communication interface 963. In addition, at least someof these functions may be mounted on the controller 951. For example,the wireless communication unit 230 receives a frame including thetentative AID and the control unit 220 causes the data processing unit210 to generate the frame with the VHT PPDU format in which thetentative AID included in the received frame is destination information.Then, the generated frame is transmitted by the wireless communicationunit 230. Therefore, by using the tentative AID in the communicationbetween the wireless access point 950 and a connected terminal, it ispossible to improve efficiency of communication between the wirelessaccess point 950 and the terminal.

5. Conclusion

As described above, according to the first embodiment of the presentdisclosure, by using the tentative AID in the communication between theSTA 100 and the AP 200, it is possible to improve communicationefficiency in communication before allocation of the AID. For example,by using the tentative AID instead of the MAC address, it is possible toreduce the size of the header without executing the association process.In addition, by omitting the association process, it is possible toreduce an overhead of communication with the AP 200.

In addition, according to the second embodiment of the presentdisclosure, for example, by using the tentative AID whose notificationis issued using the association request frame in a process ofdemultiplexing the multiplexed frame, it is possible to multiplex theassociation response frame. Accordingly, communication resources relatedto the transmission of the association response frame are efficientlyused, and thus it is possible to improve efficiency of communicationrelated to the association process.

The preferred embodiment(s) of the present disclosure has/have beendescribed above with reference to the accompanying drawings, whilst thepresent disclosure is not limited to the above examples. A personskilled in the art may find various alterations and modifications withinthe scope of the appended claims, and it should be understood that theywill naturally come under the technical scope of the present disclosure.

For example, in the foregoing embodiments, the tentative AID has beenused in the association process and the sounding process for thechannel, but the tentative AID may be used in another process in whichthe AID or information based on the AID is used. For example, thetentative AID according to each embodiment of the present disclosure isused in a power saving polling process or the like.

In addition, in the foregoing embodiments, the example in which thecommunication system includes the STAs 100 and the AP 200 has beendescribed, but one of the STAs 100 may be a communication device thathas a plurality of direct links with other STAs 100 instead of the AP200. In this case, a downlink can be said to be “simultaneoustransmission from one STA 100 to a plurality of STAs 100” and an uplinkcan be said to be “simultaneous transmission from a plurality of STAs100 to one STA 100.”

In addition, in the foregoing embodiment, the example in which the VHTNDP Announcement frame is transmitted as the second frame has beendescribed, but the BRP frame may be transmitted as the second frame.

Further, the effects described in this specification are merelyillustrative or exemplified effects, and are not limitative. That is,with or in the place of the above effects, the technology according tothe present disclosure may achieve other effects that are clear to thoseskilled in the art from the description of this specification.

Further, not only a process in which steps shown in the flowcharts ofthe above embodiments are performed in a time-series manner inaccordance with a described sequence but also a process in which thesteps are not necessarily processed in a time-series manner but areexecuted in parallel or individually is included. Also, it isself-evident that even steps processed in a time-series manner can beappropriately changed in sequence depending on circumstances.

Additionally, the present technology may also be configured as below.

-   (1)

A communication device including:

a communication unit configured to transmit a first frame including asecond association identifier decided by a communication device to whicha first association identifier is allocated and receive a second frameincluding information related to the second association identifier.

-   (2)

The communication device according to (1), in which

the second association identifier is decided within a setting range ofthe second association identifier.

-   (3)

The communication device according to (2), in which

the setting range of the second association identifier includes asetting range of the first association identifier or a setting rangedifferent from the setting range of the first association identifier.

-   (4)

The communication device according to any one of (1) to (3), furtherincluding:

a control unit configured to decide the second association identifierdifferent from the second association identifier used in anothercommunication device.

-   (5)

The communication device according to any one of (1) to (4), in which

the information related to the second association identifier includesinformation indicating the second association identifier or informationdecided on a basis of the second association identifier.

-   (6)

The communication device according to any one of (1) to (5), in which

the second frame includes a frame related to a channel informationrequest.

-   (7)

The communication device according to (6), in which

the frame related to the channel information request includes a framefor issuing a notification of transmission of a channel request frame.

-   (8)

The communication device according to any one of (1) to (7), in which

the first frame includes a frame including the second associationidentifier as transmission source information of the frame.

-   (9)

The communication device according to any one of (1) to (8), in which

the second frame includes a frame including the second associationidentifier as destination information of the frame.

-   (10)

The communication device according to any one of (1) to (9), in which

the first frame includes an association request frame, and

the second frame includes an association response frame for theassociation request frame.

-   (11)

The communication device according to any one of (1) to (10), in which

the communication unit transmits the first frame including the secondassociation identifier different from the second association identifierincluded in the first frame for which a confirmation response frame hasnot been received.

-   (12)

The communication device according to any one of (1) to (11), in which

the second frame is transmitted to a plurality of communication devicesat one time.

-   (13)

The communication device according to (12), in which

the second frame is multiplexed.

-   (14)

A communication device including:

a communication unit configured to receive a first frame including asecond association identifier generated by a communication device towhich a first association identifier is allocated and transmit a secondframe including information related to the second associationidentifier.

-   (15)

The communication device according to (14), in which

the communication unit transmits a confirmation response frame for thefirst frame on a basis of whether the second association identifier isusable.

-   (16)

The communication device according to (15), in which

whether the second association identifier is usable is determined on abasis of whether the second association identifier overlaps betweencommunication devices transmitting the first frame.

-   (17)

A communication method including: by a communication unit,

transmitting a first frame including a second association identifierdecided by a communication device to which a first associationidentifier is allocated; and

receiving a second frame including information related to the secondassociation identifier.

-   (18)

A communication method including: by a communication unit,

receiving a first frame including a second association identifiergenerated by a communication device to which a first associationidentifier is allocated; and

transmitting a second frame including information related to the secondassociation identifier.

REFERENCE SIGNS LIST

-   100 STA-   110, 210 data processing unit-   120, 220 control unit-   130, 230 wireless communication unit-   200 AP

The invention claimed is:
 1. A communication device comprising: wirelesscommunication control circuitry configured to transmit a first frameincluding an association identifier that the communication device usesin the a wireless communication network, and receive a second frame inresponse to the first frame; wherein the association identifier isshorter in data length than a Media Access Control (MAC) address,wherein the association identifier is taken from a set of valuesdifferent from a set of values in the range of 0x0001 to 0x07D7, andwherein the wireless communication control circuitry is furtherconfigured to transmit the first frame, in both a first case in whichthe communication device is associated with the another communicationdevice, and a second case in which the communication device is notassociated with the another communication device.
 2. The communicationdevice according to claim 1, wherein the second frame includesinformation decided on a basis of the association identifier.
 3. Thecommunication device according to claim 1, wherein the second frameincludes information indicating the association identifier.
 4. Thecommunication device according to claim 1, wherein the first frame is aframe including the association identifier as transmission sourceinformation of the frame.
 5. The communication device according to claim1, wherein the second frame is a frame including the associationidentifier as destination information of the frame.
 6. The communicationdevice according to claim 1, wherein the second frame is transmitted toa plurality of communication devices at one time.
 7. The communicationdevice according to claim 6, wherein the second frame is multiplexed. 8.The communication device according to claim 1, wherein the anothercommunication device is associated with a first association identifier,which is taken from a set of values in the range of 0x0001 to 0x07D7. 9.The communication device according to claim 8, wherein the second frameincludes information associated with the first association identifier.10. A communication device comprising: wireless communication controlcircuitry configured to receive a first frame including an associationidentifier from another communication device, and transmit a secondframe in response to the first frame; wherein the association identifieris shorter in data length than a Media Access Control (MAC) address,wherein the association identifier is taken from a set of valuesdifferent from a set of values in the range of 0x0001 to 0x07D7, whereinthe wireless communication control circuitry is further configured totransmit the second frame, in both a first case in which thecommunication device is associated with the another communicationdevice, and a second case in which the communication device is notassociated with the another communication device.
 11. The communicationdevice according to claim 10, wherein the second frame includesinformation decided on a basis of the association identifier.
 12. Thecommunication device according to claim 10, wherein the second frameincludes information indicating the association identifier.
 13. Thecommunication device according to claim 10, wherein the anothercommunication device is associated with a first association identifier,which is taken from a set of values in the range of 0x0001 to 0x07D7.14. The communication device according to claim 13, wherein the secondframe includes information associated with the first associationidentifier.
 15. A communication method executed in a communicationdevice comprising: transmitting a first frame including an associationidentifier that the communication device uses in a communicationnetwork; and receiving a second frame in response to the first frame;wherein the association identifier is shorter in data length than aMedia Access Control (MAC) address; wherein the association identifieris taken from a set of values different from a set of values in therange of 0x0001 to 0x07D7, and wherein the wireless communicationcontrol circuitry is further configured to transmit the first frame, inboth a first case in which the communication device is associated withthe another communication device, and a second case in which thecommunication device is not associated with the another communicationdevice.
 16. A communication method executed in a communication devicecomprising: receiving a first frame including an association identifierfrom another communication device; and transmitting a second frame inresponse to the first frame; wherein the association identifier isshorter in data length than a Media Access Control (MAC) address;wherein the association identifier is taken from a set of valuesdifferent from a set of values in the range of 0x0001 to 0x07D7, whereinthe wireless communication control circuitry is further configured totransmit the second frame, in both a first case in which thecommunication device is associated with the another communicationdevice, and a second case in which the communication device is notassociated with the another communication device.